Core A will provide the expertise, equipment and interpretive skills needed to define, at cellular resolution in vivo, the invasive phenotype of tumor cells, their corresponding expression profiles, correlated FISH, and the characterization of interactions between tumor cells and stromal cells including macrophages, all within the primary tumor and at sites of lung metastasis. This Core is the only practical way to make multiphoton imaging, and the correlated collection of invasive cells from live tumors, available to all of the projects since the expertise and equipment is unique, expensive, and cannot be duplicated for individual use. The skill required for multiphoton imaging and invasive cell collection necessitates that these methods be practiced by the same people for all projects to ensure uniformity of results so that results can be compared across animal models. Core A will also act as the liaison for expression profiling and bioinformatics with the AECOM and AECC facilities making the application of these technologies across projects uniform. Finally, Core A will support the use of high resolution FISH for in situ expression profiling. The Facilities and equipment to be dedicated to Core A are: 1. Multiphoton microscopy of tumor cells and stromal cells in vivo 2. In vivo Invasion Assay for the collection of live invasive tumor cells and stromal cells and investigation of autocrine and paracrine stimulation of invasion 3. Invasive cell typing using antibodies and PCR 4. FACs and micro-FACs 5. RNA amplification, expression profiling and Bioinformatics 6. FISH microscopy with correlated immunofluorescence